Switchable Gate Resistance

System-level design in power converters is often constrained by behaviour of the power semiconductor devices. For example, the high dV/dt from modern IGBTs must be limited to protect insulation and the DC link voltage must be limited due to switching overshoot created by high di/dt.

A unique feature of Amantys gate drives is the selectable (switchable) gate resistances: up to 63 values may be selected for each of Rg_on and Rg_off. By taking advantage of real-time bi-directional communication over the fibre-optic link, these may be used dynamically during converter operation to optimise the trade-off between dV/dt, voltage overshoot and switching loss.

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This results in a significant improvement in losses for a given dV/dt and DC link voltage, extending the converter operating envelope and offering the potential to optimise converter cost and volume.